﻿126 



NORTH AMERICAN FAUNA. 



chestnut-brown at apical two-thirds j that of head same color, running 

 on to the ears one-half their height. Beneath, basal third inclined to 

 greyish; apical two-thirds grayish fawn. Membranes almost black, 

 naked, excepting basal fourth of interfemoral membrane behind, which 

 is furnished with a small, short i^atch of glistening fur. 



Height of auricle 6'' [12.7 mm.]; height of tragus S" [6A]; length 

 of head 7" [14.8]; length of body 10" [21.1]; length of tail V 2" [30.5]; 

 length of forearm 1^ V [21 A]; length of longest finger 1' 11^^ [18.5]; 

 length of thumb 2" [4.2] ; length of tibia 5'' [10.0] ; length of foot 2^" 

 [5.3]; expanse & 1" [16.7]. Y!^^V*^> 



^'Two individuals, $ and 9 ; ^^os. 7841, 7842, Museum of Smithsonian 

 Institution, Alcohol. 



"Tres Marias, Mexico, Col. Grayson." 



Type from Piaxtla, Puebla. Adult $ (in alcohol). No, 70694, U. S. Nat. Museum, 

 Biological Survey collection. Collected Nov. 24, 1894, by E. W. Nelson and E. A. 

 Goldman. Collector's number, 7099. 



Geogra])Mc distribution. — Southern Mexico (Puebla and ' Isthmus of 

 Tehuantepec'). 



General characters. — Size, medium; length, 79 to 82; tail, 38.6 to 41; 

 forearm, 32 to 33. Calcar slender but distinct, a little shorter than free 

 border- of uropatagium, terminating in a small lobule, distinctly keeled 

 on the posterior border. Free border of uropatagium naked. Ears Ion g ; 

 when laid forward extending about 6 mm. beyond tip of nose. Wings 

 from base of toes. Feet and legs long and slender, the outstretched 

 feet reaching to within about 10 mm. of tip of tail. 



Ears. — The ears (PI. I, fig. 7) are long, and at the same time broad; 

 laid forward they reach about 6 mm. beyond tip of nose; the substance 

 of the conch thin and translucent. Anterior border strongly convex 

 from base to a little below middle, then straight or very slightly con- 

 vex to the rather broadly rounded off' tip. Posterior border concave 

 below tip to about middle, where it bends abruptly outward, then grad- 

 ually convex to base. A very faintly indicated basal notch and basal 

 lobe. About 5 mm. above the crown and an equal distance from the 

 tip of the ear conch in the male is developed a conspicuous, flattened- 

 pyriform, glandular thickening with the large end toward the anterior 

 margin of the ear and the main axis nearly perpendicular to that of the 

 auricle. The thickened mass is 5 mm. in length, 4 mm. wide at the 

 broad end, 2 mm. at the narrow end, and 1 mm. thick. It is most con- 

 spicuous on the dorsal side of the ear, where, although not different in 

 color from the rest of the ear, it is noticeably raised above the surface, 

 and the boundaries are sharply marked. On the inner side of the 

 ears the thickenings are less definite in outline, but are noticeably 

 paler thau the surrounding integument. When these structures are 

 examined with a lens it is seen that they are thickly covered on the 



RHOGEESSA GRACILIS sp. nov. 



